When glycol is heated with dicarboxylic acid, the products are:

Options

A. Polyesters
B. Polyethers
C. Polyethylene
D. No reaction at all

Answer

To determine the products formed when glycol is heated with a dicarboxylic acid, we can follow these steps:

### Step 1: Identify the Reactants
Glycol, specifically ethylene glycol, has the structure:
\[ \text{HO-CH}_2-\text{CH}_2-\text{OH} \]
This means it has two hydroxyl (-OH) groups.

A dicarboxylic acid contains two carboxyl (-COOH) groups. For this example, we can consider terephthalic acid, which has the structure:
\[ \text{HOOC-}C_6\text{H}_4-\text{COOH} \]

### Step 2: Understand the Reaction Type
When glycol is heated with a dicarboxylic acid, a condensation reaction occurs. In this type of reaction, water is eliminated as the two reactants combine to form a larger molecule.

### Step 3: Mechanism of the Reaction
During the heating process:
- One -OH group from glycol and one -H from the carboxylic acid will be removed, resulting in the loss of water (H₂O).
- This leads to the formation of an ester linkage (-COO-).

### Step 4: Formation of the Product
The reaction results in the formation of a polymer known as a polyester. The general structure of the polyester formed from ethylene glycol and a dicarboxylic acid can be represented as:
\[ \text{[-O-CH}_2-\text{CH}_2-\text{O-CO-]}_n \]
where n indicates the number of repeating units in the polymer.

### Step 5: Conclusion
The product formed when glycol is heated with a dicarboxylic acid is a polyester.

### Final Answer
The products are polyesters.

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